A promising approach to drug addiction

With the help of a grant, a New Zealand researcher intends to explore how a vaccine for drug addiction could become a reality.

April 1, 2019

A Victoria University of Wellington scientist hopes to bring us a major step closer to a vaccine for drug addiction, with the help of an Explorer Grant from the Health Research Council of New Zealand.

Scientists have been trying to create vaccines for treating drug addiction since the 1970s, but so far trials in humans have had disappointing results, says Dr Benjamin Compton. He believes the lack of efficacy comes down to vaccine design, not the concept itself.

With a background in chemistry and experience in developing immunotherapy treatments for cancer, asthma,influenza and malaria, Dr Compton will construct a synthetic vaccine that works in a completely different way to others trialled in this field.

Working with immunologist Dr Lisa Connor, Dr Compton is pioneering a vaccine platform that can generate an immune response to small drug-like compounds. His concept is to circumventthe need for protein-based activation of the immune system to drive this response.

The end-goal is to instruct the body’s immune system to recognise a specific drug when it enters the bloodstream, and to treat it like a toxin: that means antibodies would bind to the targeted drug in the periphery and prevent it from crossing the blood-brain barrier where it would normally interact with receptors and trigger ‘a high’.

“Achieving this would herald a new paradigm in immunopharmacotherapy,” says Dr Compton. “And importantly, we’re aiming to design a vaccine that can be manufactured en masse, at low cost.”

The HRC’s chief executive, Professor Kath McPherson, says this research addresses a major issue of concern for individual and public health. “Drug addiction is a serious problem worldwide, which not only results in personal harm, death and reduced quality of life, but also costs our health system hugely in hospital admissions and emergency attendances, treatment and counselling.

“A vaccine could well be the way of the future. If Dr Compton can deliver proof of concept, it could be a ground-breaking step towards developing a vaccine in the future.”

Vaccines are one of the most cost-effective and powerful health interventions available, notes Dr Compton, and he believes it should be possible to vaccinate against drug addiction.

“Ultimately what we’re trying to do is generate a robust B-cell response (an antibody response) to specific drug targets.”

Traditionally this is done by first generating a T-cell response (those white cells that defend us against infection and disease) which in turn enhances the B-cell response. However, due to the complexity of the human body, generating the desired T-cell response can be tricky. Cellular processing and presentation of proteins varies from person to person which, in part, may be responsible for past failures to develop vaccines for drugs of abuse.

Dr Compton’s novel vaccine construct should improve the T-cell response or, even better, directly activate B-cells independent of a T-cell response. But even if his vaccine can activate B-cells directly, that in itself may not be enough; the key to making this kind of vaccine effective is to ensure it also drives a memory response to the drug.

“We are trying to understand the simplest way to activate B cells so that we can invoke a memory response to compounds which would otherwise not be recognised by the immune system. How can we make this technology a reality?” Dr Compton will be testing his vaccine on mice, and if he can prove that the concept works, it could be a game-changer.

“This technology will be really helpful for those addicts who want to break free of their addiction. Should that person come into contact with the drug, a vaccine will ensure there is no reward from the drug-taking behaviour.”

Dr Compton was one of 15 researchers to receive a Health Research Council 2019 Explorer Grant, valued at $150,000 each. The Explorer Grant scheme seeks to attract and fund transformative research ideas with the potential for major impact on healthcare.

More severe than the common cold, influenza can cause serious complications such as pneumonia, especially among the elderly, the very young and pregnant women. Experts recommend getting vaccinated as soon as possible.